Fiber optic voltage conditioning

Abstract

A fiber optic voltage conditioner, and method therefor, generally relate to voltage conditioning. In such a fiber optic voltage conditioner, there is a laser, and an optical circulator is coupled to receive a light signal from the laser. A controller is coupled to the laser and is configured to generate first control information for wavelength-drift control of the laser. A data acquisition module is coupled to the controller and is configured to generate second control information for the controller for adjustment of the first control information. A photodetector is coupled to the optical circulator to receive a returned optical signal and is coupled to the data acquisition module to provide an analog output signal thereto. The photodetector is configured to generate the analog output signal responsive to the returned optical signal. The data acquisition module is configured to generate the second control information using the analog output signal.

What is claimed is: 
     
       1. A system, comprising:
 a controller configured to be coupled to a light source and configured to generate first control information for wavelength-drift control of the light source; 
 a data acquisition module coupled to the controller and configured to generate second control information for the controller for adjustment of the first control information; 
 a photodetector to receive a returned optical signal and coupled to the data acquisition module to provide an output signal thereto; 
 the photodetector configured to generate the output signal responsive to the returned optical signal; 
 the first control information being for both thermoelectric (“TEC”) tracking and current tracking of the light source for the wavelength-drift control for the output signal to provide wavelength-drift compensating for a range from 0 to 20 kHz to provide temperature sensing; and 
 the data acquisition module configured to generate the second control information using the output signal. 
 
     
     
       2. The system according to  claim 1 , wherein the data acquisition module is configured to generate proportional-integral-derivative (“PID”) feedback information to generate the second control information. 
     
     
       3. The system according to  claim 2 , wherein the data acquisition module is configured to record the output signal of the photodetector being below at least one threshold therefor for generation of the PID feedback information. 
     
     
       4. The system according to  claim 3 , wherein the PID feedback information includes PID current error information and PID TEC error information. 
     
     
       5. The system according to  claim 4 , wherein the data acquisition module is configured to respectively add a current set voltage and a TEC set voltage to the PID current error information and the PID TEC error information for the generation of the second control information. 
     
     
       6. The system according to  claim 1 , wherein:
 the wavelength-drift control of the light source is to compensate for drift of a Bragg wavelength; and 
 the second control information is used to adjust the first control information to tune wavelength of the light source for the wavelength-drift control of the light source. 
 
     
     
       7. The system according to  claim 6 , wherein the output signal is a first analog output signal, and wherein the system further comprises an acoustic emission data acquisition system coupled to the photodetector to receive a second analog output signal therefrom. 
     
     
       8. The system according to  claim 7 , further comprising a plurality of photodetectors and a plurality of controllers coupled to the data acquisition module and configured to generate multi-channel fiber optic voltage conditioning. 
     
     
       9. A method for fiber optic voltage conditioning, comprising:
 generating first control information by a controller responsive to a light source for wavelength-drift control thereof; 
 generating second control information by a data acquisition module coupled to the controller; 
 adjusting the first control information by the controller responsive to the second control information; 
 receiving a returned optical signal by a photodetector; 
 generating an output signal by the photodetector responsive to the returned optical signal; and 
 monitoring temperature by the data acquisition module coupled to the photodetector using thermoelectric (“TEC”) and current tracking of the light source responsive to the first control information including for the wavelength-drift control for the output signal to provide wavelength-drift compensating for a range from 0 to 20 kHz. 
 
     
     
       10. The method according to  claim 9 , wherein the generating by the data acquisition module of the second control information is for the output signal, the method further comprising:
 generating proportional-integral-derivative (“PID”) feedback information by the data acquisition module for the generating of the second control information; and 
 wherein the generating of the PID feedback information comprises recording by the data acquisition module of the output signal of the photodetector responsive to the output signal being below at least one threshold therefor. 
 
     
     
       11. The method according to  claim 10 , wherein the PID feedback information includes PID current error information and PID TEC error information. 
     
     
       12. The method according to  claim 11 , further comprising adding by the data acquisition module a current set voltage and a TEC set voltage to the PID current error information and the PID TEC error information, respectively, for the generating of the second control information. 
     
     
       13. The method according to  claim 9 , wherein the wavelength-drift control of the light source is to compensate for drift of a Bragg wavelength. 
     
     
       14. The method according to  claim 13 , wherein the adjusting of the first control information is to tune wavelength of the light source for the wavelength-drift control of the light source responsive to the second control information. 
     
     
       15. The method according to  claim 9 , wherein the light source is a broadband light source, the method further comprising propagating light from the light source in a fiber optic line to at least one Fiber Bragg grating sensor.